There are definitely times when one needs to dress nicer/differently than they would at other times. If you are going to some fancy schmancy restaurant, you should dress nicer than if you are going to McDonalds. A craftsman can not dress the same as a lawyer would for two reasons. For one, his/her clothes would get ruined but the main reason is that it would be too dangerous to dress like that. You get your tie caught up in a lathe, drill press or other power tool, and you could end up on the TV show, "1000 Ways to Die".